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Novel processes have recently been developed that provide for the enhancement of ozonation through combination with electrochemical treatments. These are processes that can be included among those defined as advanced oxidation processes as they proceed via electrogeneration of highly oxidizing radical species.These processes are generally carried out by sparging ozone in both divided and undivided electrochemical cells in order to promote its decomposition through different mechanisms, depending on the electrode materials adopted, and in some cases still debated.This mini review presents the most recent advances in the field of electrochemically assisted ozonation.In particular, the first section is focused on the process known as electroperoxone (EP) where the ozone decomposition is enhanced by the adoption of carbon-based cathodes, due to the electrogeneration of hydrogen peroxide, while the second section is focused on the process that implies ozonation in a cell adopting metal-based cathodes. 相似文献
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The use of polyhedral oligomeric silsesquioxane (POSS) as a soluble support in organic synthesis is reported. A POSS-bound isocyanate was readily synthesised in one step from commercially available starting materials and was isolated in high yield and purity by simple filtration. It was found to perform well as a scavenger for excess amine in the solution phase synthesis of amides and sulfonamides, allowing product isolation in high yield and purity. 相似文献
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Meritxell Guinó 《Tetrahedron letters》2005,46(40):6911-6913
Three phosphine-functionalised polymer resins were used as scavengers of palladium catalysts from Buchwald-Hartwig aryl amination reactions. The purity of the products was assessed, and residual palladium analysed by ICP-AES. Scavenging efficiencies of up to >98.5% were demonstrated. 相似文献
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Nucleotide/Tb coordination polymer nanoparticles as luminescent sensor and scavenger for nitrite ion
Newly emerged metal organic coordination polymers have aroused the great interest in designing tailored functional materials. In this study, multiple functional components, luminescent Tb3+ ion, nucleobase and antenna molecule, were integrated in a single material and prepared into a responsive nanoparticle for nitrite. The terbium coordination polymer nanoparticles made of this kind of material have the dual functions of recognition and transduction and obey a preset sensing mechanism without a post-functionalization of common materials. As the result of the tailored, the terbium coordination polymer nanoparticles are highly sensitive and selective to nitrite by means of Dexter energy transfer between Tb3+ ion and nitrite, and can be used for the scavenger for nitrite in aqueous solution. The detection limit, dynamic range and removal capacity of U–Tb–OBBA CPNPs for nitrite are 0.3 µM, 0.3–470 µM and 4.44 mg per gram of particles, respectively. Metal organic coordination polymers show an attractive potential in constructing smart sensing materials. 相似文献
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A. S. Aliewi R. Mackay A. Jayyousi K. Nasereddin A. Mushtaha A. Yaqubi 《Transport in Porous Media》2001,43(1):195-212
The Pleistocene aquifers are important sources of water supply in both the Gaza and Jericho areas of Palestine. The aquifers are saline with freshwater lenses floating on saline bodies of water. It is important to investigate how to exploit these freshwater lenses without causing unnecessary mixing of the fresh and saline waters. The objective of this research is to investigate the feasibility of applying skimming and scavenger pumping as a means to exploit the freshwater lenses and to control saline water upconing in the aquifers. This study is the first to examine the movement of fresh and saline waters underneath skimming and scavenger wells in the aquifers of Gaza and Jericho. Two simulation models that couple density-dependent fluid flow and solute transport have been used to simulate and predict the movement of saltwater under different hydrogeological and operational conditions of skimming and scavenger wells in the two aquifers. The results show (for the Jericho Aquifer) that: the location of well screen has a strong control on the steady-state position of the fresh/saline water transition zone; the upconing mechanism appears to continue under skimming pumping until saline water enters the well screen even when the pumping rate is reduced; and for better salinity control it is necessary to place well screen against the gravel layers only and locate one screen segment in the saline water zone. The study shows (for the Gaza coastal aquifer) that the most important parameters affecting the movement of saline water under scavenger pumping are the relationship between recharge and pumping rates, the location of the well screen within the saturated thickness, the vertical permeability; and the transverse dispersivity. This study shows that saltwater upconing in Gaza aquifer can be controlled by operating a second well in the saline water zone so that the optimal ratio between saline water and freshwater pumping is 1:2 respectively. 相似文献
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Nicola Galaffu 《Tetrahedron letters》2005,46(5):859-861
Isocyanate resins are used in polymer assisted solution-phase synthesis, however, their use is limited by their high cost and often unfavourable reaction profiles. Here a route to prepare efficient supported isocyanate resins from aminomethyl resin and inexpensive diisocyanates is reported and compared to commercially available isocyanate resins. 相似文献
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Anderson DR Duryee MJ Garvin RP Boska MD Thiele GM Klassen LW 《Magnetic resonance imaging》2012,30(1):96-103
Objective
Perfluorocarbon-exposed sonicated dextrose albumin microbubbles (PESDA) binds scavenger receptors and can be noninvasively imaged. To enhance imaging, gadolinium (Gd)-labeled PESDA was developed and tested in a model of vascular inflammation by magnetic resonance imaging (MRI).Methods and Results
Purified human serum albumin (HSA) (5%) was labeled with Gd via the covalent binding of diethylenetriaminepentacetic acid. Abdominal aortic tissues in Sprague-Dawley rats (n=5 per group) were analyzed by 7-T MRI and scanning electron microscopy to evaluate PESDA binding. Labeling-purified 5% human albumin resulted in an average of 16.1 Gd atoms per albumin molecule as determined by atomic absorption. Forty-eight hours after balloon angioplasty, aortic tissue was enhanced with Gd-PESDA as compared to control tissue. 7-T MRI of explanted tissues was sensitive to the detection of retained PESDA. Enhancement of aortic tissue in vivo was present albeit to a lesser extent than explanted tissue from the same animals.Conclusions
HSA was successfully labeled, and an albumin-based microbubble with Gd was synthesized. This contrast agent, Gd-PESDA, may serve as an additional agent for the MRI evaluation of innate inflammation and used to noninvasively image early vascular pathophysiologic processes.Condensed Abstract
In this study, Gd-PESDA microbubbles and were synthesized and shown to detect the binding of these microbubbles using MRI in injured aortic tissue. The method for synthesizing Gd-PESDA is detailed, and the proposed utility of this new contrast agent is discussed. 相似文献10.
应用约束刻蚀剂层技术(CELT)对GaAs进行电化学微加工. 研究了刻蚀溶液体系中各组成的浓度比例、GaAs类型、掺杂以及阳极腐蚀过程对GaAs刻蚀加工过程的影响. 循环伏安实验表明, Br-可以通过电化学反应生成Br2作为刻蚀剂, L-胱氨酸可作为有效的捕捉剂. CELT中刻蚀剂层被紧紧束缚于模板表面, 模板和工件之间的距离小于刻蚀剂层的厚度时, 刻蚀剂可以对GaAs进行加工. 利用表面具有微凸半球阵列的导电模板, 可以在不同类型GaAs上加工得到微孔阵列. 实验结果表明: 在相同刻蚀条件下, GaAs的加工分辨率与刻蚀体系中各组分的浓度比例有关, 刻蚀结构的尺寸随着刻蚀剂与捕捉剂浓度比的增加而增大; 在加工过程中, p-GaAs相对于n-GaAs和无掺杂GaAs受到阳极氧化过程的影响较为显著, p-GaAs表面易生成氧化物层, 影响电化学微加工过程. X射线光电子能谱(XPS)和极化曲线实验也证明了这一点. 相似文献